ISSN 2394-3777 (Print) ISSN 2394-3785 (Online) Available online at www.ijartet.com International Journal of Advanced Research Trends in Engineering and Technology (IJARTET) Vol. 6, Issue 5, May 2019
Image Forgery Detection using Adaptive Oversegmentation and Feature Point Matching Angel Jeba Rathna.S1, Priya.M2, Sangeetha.N3, Vellathai.P4, Dr.Anitha.A5
1 (Dept. of IT, UG Scholar, Francis Xavier Engineering College, angeljr8778@gmail.com) (Dept. of IT, UG Scholar, Francis Xavier Engineering College, priyadeekshi2408@gmail.com) 3 (Dept. of IT, UG Scholar, Francis Xavier Engineering College, sangeethasivayam2024@gmail.com) 4 (Dept. of IT, UG Scholar, Francis Xavier Engineering College, pvedhika04@gmail.com) 5 (Dept. of IT, Professor, Francis Xavier Engineering College, dr.aanitha@yahoo.com) 2
Abstract: A novel copy–move forgery detection scheme using adaptive oversegmentation and feature point matching is proposed in this paper. The proposed scheme integrates both block-based and keypoint-based forgery detection methods. First, the proposed adaptive oversegmentation algorithm segments the host image into nonoverlapping and irregular blocks adaptively. Then, the feature points are extracted from each block as block features, and the block features are matched with one another to locate the labeled feature points; this procedure can approximately indicate the suspected forgery regions. To detect the forgery regions more accurately, we propose the forgery region extraction algorithm, which replaces the feature points with small super pixels as feature blocks and then merges the neighboring blocks that have similar local color features into the feature blocks to generate the merged regions. Finally, it applies the morphological operation to the merged regions to generate the detected forgery regions. The experimental results indicate that the proposed copy–move forgery detection scheme can achieve much better detection results even under various challenging conditions compared with the existing state-of-the-art copy–move forgery detection methods. I.
INTRODUCTION
With the development of computer technology and image processing software, digital image forgery has been increasingly easy to perform. However, digital images are a popular source of information, and the reliability of digital images is thus becoming an important issue. In recent years, more and more researchers have begun to focus on the problem of digital image tampering. Of the existing types of image tampering,a common manipulationof a digital image is copy-move forgery [1], which is to paste one or several copied region(s) of an image into other part(s) of the same image. During the copy and move operations, some image processing methods such as rotation, scaling, blurring, and compression. II. IMAGE FORGERY We have performed a large number of experiments to seek the relationship between the frequency distribution of the host images and the initial size of the superpixels to obtain good forgery detection results. We performed a fourlevel DWT, using the ‘Haar’ wavelet, on the host image; then, the low-frequency energy ELF and high-frequency energy EHF can be calculated using (1) and (2), respectively. With the low-frequency energy ELF and high-
frequency energy EHF, we can calculate the percentage of the low-frequency distribution PLF using (3), according to which the initial size S of the superpixels can be defined. Where S means the initial size of the superpixels; M × N indicates the size of the host image; and PLF means the percentage of the low-frequency distribution. In summary, the flow chart of the proposed Adaptive Over-Segmentation method is shown in Fig. 3. First, we employed the DWT to the host image to obtain the coefficients of the low- and high-frequency sub-bands of the host image. Then, we calculated the percentage of the low-frequency distribution PLF using (3), according to which we determined the initial size S, using (4). Finally, we employed the SLIC segmentation algorithm together with the calculated initial size S to segment the host image to obtain the image blocks. In this section, we extract block features from the image blocks (IB). The traditional block-based forgery detection methods extracted features of the same length as the block features or directly used the pixels of the image block as the block features; however, those features mainly reflect the content of the image blocks, leaving out the location information. In addition, the features are not resistant to various image transformations.
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